But some time ago, several chinese seller tried to fool me in direct messaging saying “close the appelation and I’ll return money to your PayPal”

I've had American sellers do the same thing on Amazon. I've had them lie about a product being new on their listing and refuse to correct the mistake only to try to bribe me to take my bad review of them down (even then their offer wasn't sufficient to fix my problem). It's not about nationality, it's just scumbags being scumbags and those come from all nations.